This invention relates to liquid-filled force and displacement transfer cable systems, and more particularly to transfer cable systems which are self-contained, complete and designed to receive and reproduce external mechanical signals at selected points remote from each other with the transmitting medium being a non-compressible liquid. The systems are filled in their entirety with a suitable liquid which is preferably sealed and non-replenishable.
Transfer cable systems generally find application where accurate but remotely controlled force or displacement transfers are required, and where a rigid or inflexible cable would not be feasible. Such cable systems could be adapted to control fluid power circuits, to effect manipulation of switches and gears, or to insure the precise positioning of controls (e.g., where forces under 250 lbs. are applied and linear piston displacement of approximately 3 inches is required). Typical force and displacements associated with this type of cable system are forces of less than 100 lbs. and displacements up to 11/2 inches. More specifically, such cable systems might find application in aircraft, marine or power plant related machinery. In providing a means for transferring signals to actuate controls, for example, the cable system will not rely on any source of external power to effectuate such a transfer. The cable system merely receives and reproduces mechanical motions as signals, and would therefore allow manual manipulation of remotely located controls during electrical power failures or the like. The necessity of assuring accurately predictable force and displacement transfers for both push and pull inputs made from either end of a single cable have not been assured in the past.